Riddle



v. J. DAvls Sept. 17,119.29.`

RIDDLE Filed April 8, 1927 2 Sheets-Sheet v. J; DAvls Sept. 17, 1929.

RIDDLE Filed April 8. 1-9'27 2 Sheets-Sheet 2 A TTOR/VEY the 20 APatented Sept. 17, 1929 UNITED STATES vnnNoN J. Davis, or Burano, mawYou ummm A i appunti mea April s, 1927. serial m. 182,000.

This invention relates to improvements in riddles, proposing aconstruction which is especially intended for, altho not necessarilylimited to, use in foundries for screening moldin sand and embodies amechanically operate screen adapted for arrangement under the hopperfrom which the sand is discharged and over the chain of molds wherebythe sand is screened as it issues 1o from the hopper. Y

One object of'the invention is to rovide a combination and arrangement oparts characterized by the location of the screen operating andsupporting mechanism wholly beyond one end of the screen, theelimination of all overhead and base supports,

and adequate provision for takingl the weight of the screen box and thesand t erein from operating shaft.

rther object is to provide operating mechanism by which the screen has apath, speed and manner of vibrations such that it tends to break up mostof the lumps in` the sand and thus enables the effective use of amaximum quantity of sand.

A still further object is to provide for an arragement of the screen boxwhereby it may. be quickly and easily inverted for the purpose ofdischarging the accumulation on the screening fabric whenever such anaccumulation has reached a point where it is desirable that the fabricbe cleaned.

An embodiment of the invention is illustrated in the accompany drawingsin which:

Figure 1 is a plan view.

Figure 2 is a side elevation. Figure 3 is an enlarged side elevation ofthe motor and the supporting elements for the screen box.

Figure 4 is a partial front elevation of the motor and the supportingelements for the screen box,- said elementsbeing shown partly invertical central section.

The screen box (not shown) is supported in a suitable horizontal frame 1having a thumbscrew 2 by which said box is secured and the operatingmechanism is' located wholly beyond one end of this frame and is soconstructed that it imposes substan- `tially no weight load upon theoperating shaft. The riddle as an entirety is mounted on a suitablesupport from which it extends laterally. This lsupport is preferabl aswlnglng support which comprises a xed bracket 3, a swinging bracket 4and a pivot pin 5 whereby the mddle may be swun to one side when its useis not required. g1`he swinging bracket 4 includes a verticle supportlngplate 6 to which there is secured by olts 7 the base 8 of an electricmotor 9. The shaft 10 of the motor 9 vibrates an element by which theframe 1 is directly supported, said element referably being in the formof a U-shape hanger 14 having vertical arms 13 and a bridge piece 15attached to the arms by bolts 16. Said shaft preferably carries at eachend an operating eccentric 11 and these cooperate with eccentric straps12 provided on the arms 13. The bridge piece 15 is formed with alongitudinal sleeve 17 for the support of a stem 18 by which the frame 11s carried, ksaid frame having a collar 19 in which said stem is fittedand secured by a pin 20. The eccentric straps 12 are shown in detail inFigure 4 and are each composed of rings secured together by bolts 21,the rings being formed to delimit an internal chamber for a suitableball bearing 22 and also being provided with suitable packing 23. 4

The hanger 14 is acted on by suitable equahzing springs 24. The arms 13are provided with rearward extensions 25 which carry a transversey bar26 arranged behind the plate 6 and to which the springs 24 areconnected, said springs at their remote ends being connected to the topand bottom lugs of the bracket 4, preferabl by adjusting eyes 27. Thebracket 4 inclu es at its sides vertical reenforcing lian es 28 andthese are provided with enlarge circular openings 29 through which thebar 26 extends, the diameter of these openings permitting movements ofthe bar in all dlrections incident to the vibration of the hangers 13.The bracket 4 is provided at its upper end with a forwardly projectingarm 30 and a supporting spring 31 has its upper end connected to an eye32 carried by the arm 30 and its lower end connected to an eye 33attached to a forward 10 extension 34 of. the sleeve 17, the spring 31,aided by the springs 24 serving to take the weight ofthe` parts'f'ffromthe eccentrics 11 and thus minimize wear. The principal function of thesprings 24 as equalizing springs is to hold the hanger 14 within anormal range of angles during its vibrations by the motor shaft. In thisfunction the springs limit the vertical movements of the bar 26 withoutsubstantially limiting its horizontal movements whereby the frame 1V isprogressively canted in fore and aft directions during its oppositevertical vibrations. The path in which the frame 1 vibrates issubstantially elliptical.v The vertical movements of the frame in itspath of vibration are more rapid than the fall of the sand. Consequentlythe screening fabric will strike the sand with such force as to tend tobreak the lump and cause them to rebound, this action being aided by thecanting of the frame as described. The canting action of the frame alsoaids in promoting the fore and aft shifting of the mass of sandrelatively to the screening fabric so as to secure rapid and mosteffective screening re- Y sults.

The stem 18 is mounted whereby it may be e turned in the sleeve 17,butis suitably held against accidental turning movement. Thus the stemhas direct bearing in a suitable bushing 35 which is litted within thesleeve but is suliicientlyshort to provide a chamber fpran expansionspring 36 bearing at its ends against said bushing and against "a head37 at the'rear end of -the stem. The

A hea sleeve extension 34 is formed in its edge face with a notch 38 andthe collar 19 is formed with a projection 39 which under thepressure ofthe sprin 36 is caused normally to engage in the notc the latter andtheprojection preferably being cam faced. When it is desired to clean the Yscreening fabric the frame 1, which is secured to the stem 18 by the pin20, is turned upside downwith reference torsaid'stem as an axis for theurpose of 'dislodging from thscreening fa ric the accumulated matter. Inthis turning movement the projection 39 'rides along the inclined'face`of the notch and moves the stem.

axially against 'the pressure of the spring 36. When the accumulatedmatter has been dischargedthe frame 1 is restored to its originalposition in which it is held by the engagement of theprojection 39 inthe notch 38.

It will be observed that frame 1 is operated and entirely supported bymechanism ,which is located wholly beyond one end thereof and'that: thespace above and belowv said frame is entirely unobstructed whilerat'thesame time the operating and supporting mechanism is such that no overorground-attached supporting parts 'are required; Inr view of thesecharacteristics lthe frame 1 may be instantly moved to a positionbetween Ythe hopper and the chain of molds Without any interference withsaid hopper or molds and in such position rapidly vibrated for thepurpose of screening the sand as it is delivered from the hopper and inthe course of its passage to the molds.

vHaving fully described my invention, I claim:

1.. In a riddle the combination with a screen bearing frame of operatingand supporting mechanism located wholly beyond one end thereof andincluding an element supporting said frame and connected to one endthereof, a motor, means operativelyv connecting the shaft of the motorand said element to vibrate the latter in an elliptic path and means forcausing the frame to cant fore and aft at periods of its vibration.

2. In a riddle the combination with a screen bearing frame of operatingand supporting mechanism located wholly beyond one end thereof andincluding a motor, a hanger pendant from the motor shaft and connectedto one end of said frame, and eccentric and strap connections betweensaid shaft and the hanger to vibrate the latter.

3. In a riddle the combination with a screen bearing frame of operatingand sup- `porting mechanism located vWholly beyond one end thereof andincluding a motor an element supporting said frame and connected to oneend thereof, means operatively connecting the shaft of. said motor andsaid element to vibrate the latter, and equalizing means for determiningthe angular positions of said element during its vibrations.

4. In a riddle the combination with a screen bearing frame of operatingand supporting mechanism located wholly beyond one end thereof andincluding a motor, av

element supporting said frame and con' nected to one end thereof,eccentric an'd strap connections between the shaft of said motor andsaid element to vibrate, the latter, equalizingmeans for determining theanguvlar positions of said element during its vibrations, and a springsupport for said element to take the weight thereof and of said framefrom the motor shaft.

6. In a riddle the combination with Aa screen bearing frame of operatingand supporting mechanism located wholly beyond one end thereof andincluding a motor, a the motor and said element to vibrate the lathangerpendant from the motor shaft and ter vertically.

connected to one end of said frame, eccentric and strap connectionsbetween said shaft and the hanger to vibrate the latter, equalizingsprings acting on said element for determining its angular positionsduring its vibrations, and a spring su port for said elementv to takethe weight t ereof and of said frame from the motor shaft.

7. In a riddle the combination with a screen bearing frame of operatingand supporting mechanism located wholly beyond one end thereof andincluding a motor, a hanger havin arms endant from the motor shaft, theanger eing connected to one end of said frame, eccentric and strapconnections between said shaft and the hanger to vibrate the latter, thearms having rearward extensions, a cross bar connecting said extensions,and equalizing springs acting on said bar at opposite" sides thereof fordeterrnining4 the angular positions of' th hanger during its vibrations.

8. In a riddle the combination with a screen bearing frame of opcratinand supportmg 'mechanism located who ly beyond one end thereof andincluding a motor, a' hanger having arms pendant from the motor shaftandv a bridge piece connecting the arms, a centrally located stempro'ecting forward from the bridge piece an connected to one end of theframe, eccentric and stra connections between the motor shaft an saidarms to vibrate the han r, and a su porting sprin acting on said stem tota e the weight o the hanger and said frame from the motor shaft.

9. In a riddle the combination with a screen bearing frame of operatingand sup- In testimony whereof I hereby aiix my signature.

porting mechanism located wholly beyond one end thereof and includin amotor, a hanger having arms pendant om the motor shaft and 'a bridgepiece connecting the arms, a centrally located stem projecting forwardfrom the bridge piece and connected to one end of the frame, eccentricand strap connections between the motor shaft and said arms to vibratethe hanger, a supporting spring acting on said stem to take the weightof the hanger and said frame from the motor shaft and equalizing springsacting on said hanger for determining its angular positions during itsvibrations.

10. In a riddle the combination with a screen bearing frame of operatingand supporting mechanism located wholly beyond one end thereof andincuding an element supporting said frame and connected to one endthereof, means arranged to hold said frame in its normal position onsaid element and to permit its inversion for the purpose of cleaning thescreen, a motor, and means operatively connecting the shaft of VERNON J.DAVIS.

